Friction-clutch.



N0. 882,693. PATENTED MAR. 24, 1908. A. KINGSBURY. FRICTION GLUTGH.

APPLICATION FILED MAR. 6' 1905.

Mim ann,

INVENTOR UNITED STATES PATENT OFFICE.

ALBERT KINGSBURY, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

FRICTION-CLUTCH.

Specification of Letters Patent.

Patented March 24, 1908.

To all whom it may concern.

Be it known that I, ALBERT Kmosaunr, a citizen of the United States, and a resident of Pittsbur in the county of Allegheny and State 0 Pennsylvania, have invented a new and useful Improvement in Friction- Qlutches, of which the following is a specification.

My invention relates to friction clutches and dparticularly to such clutches as are depen ent upon centrifugal action for their operation.

The object of m invention is to provide a clutch which shal be automatically adjustable to transmit energy to a rotata le member at various predetermined rates of shaft rotation in either direction with equal efiicienc and which shall be inexpensive and simp e in construction, and effective in operation.

As heretofore constructed, centrifugally operated friction clutches were usually dependent u on the movement of lever mechanism am attached weights, to cause a binding ring to engage an inner cylindrical surface of a cooperating member. With such devices the speed of shaft rotation at which a single clutch member would operate to engage its cooperating member varied in different instances over comparatively wide limits and in many cases clutches apparently similar, and com irising similar parts throu hout, showed wirle differences in the speed of shaft rotation at which they actuated the driven member. These variations and the factor of uncertainty conse uently introduced were'due to the fact t at any slight variation in the distance between the point of support and the point of application of the lever made a comparatively great variation in the action of the clutch, and the binding ring usually began to hear at a single oint so that action was transmitted so sudr enly as to cause a iflk on the pulley load. Furthermore, suc devices do not operate with equal efficiency for both directions of shaft rotation.

My invention which corrects the principal defects in centrifugally operated friction clutches, as formerly constructed, by insuring a more uniform contact between the friction ring and the cooperating member, and an operation which is uninfluenced by slight mechanical variations, is illustrated in the accompanying drawings of which Fi e 1 is an end elevation of a clutch constructed in accordance therewith, the driven member being shown as a pulley and in crosssection on line II of Fig. 2, in order to disclose the clutch mechanism. Fig. 2 is a longitudinal, sectional view of a clutch pulley like that shown in Fig. l as applied to the shaft of an electric motor that 1s shown in side elevation.

My invention, as illustrated, comprises in general a driven member 1, a supporting disk 2, a friction ring 3 and a holding spring 4.

The supportin r disk 2 is rigidly fastened to the shaft 5 of a riving motor 6, by any convenient means; such for example as a key 7 and a set screw 8 which en age the hub 9 of the ring and is provided wit 1 an annular surface 10 having an annular roove 11, an annular flange 12 and a sli ht y-projecting hub 13 which is opposite the ub 9.

. The friction ring 3 is provided with an annular surface 14 and an annular pro'ection 15 which on age, respectively, wit 1 t e surface 10 and t e groove 11 of the disk 2, when the clutch is at rest. A portion of the ring 8 is cut away to form an opening 16 which allows the rin to be sprung to slightly separate the on s of the remaining are so that the projection 15 may be brought into engagement with the groove 11 m the supporting disk 2. The two ends of the ring 3 are drawn toward each other after the ring is in position on the supporting disk 2, by the spring 4 which is fastened to one of said ends by a in 17 and to the other end. by a screw 18 w ich may be adjusted to vary the tension of the springs A projection 19 on the disk 2 engages the opening 16 in the ring 3 and serves to prevent rotation of the ring 3 upon the disk 2.

The ring 3 is provided with a plurality of curved slots 20, 21, 22, 23 and 24 which are concentric with the outer and inner surfaces of the rin and are approximately equally spaced in t e remaining material of the rin 1 after provision is made for the spring 4 and its supports. The portionof the ring 3 between the slots 20, 21, 22, 23 and 24 and the inner surface 14 is cut to form radial slots 25, 26, 27 28 and 29 the dimensions and location of which are determined by the amount of material that must be removed in order to staticall balance the ring. The radial slots inateria y increase the flexibility of the ring without decreasing its weight to any considerable extent.

The member 1 embodies a disk 30 that is perpendicular to the center line of the shaft 5, and is provided with an annular projection or flange 31 at its edge, the inside diameter of which is slightly greater than the normal outside diameter of the rin 3 so that when the member 1 is on the sha t 5 to which the disk support 2 is keyed, the flange 31 fits loosely over the ring 3 and the hub engages with the disk 30 to prevent lateral movement of the member 1 along the shaft toward the motor. A ring 32 may be fastened to the shaft in the usual manner to keep the member 1 from moving along the sha t 5 in the other direction. As the ring 3 reaches a predetermined rate of s eed, corresponding to the speed of the she t 5 of the drivin motor 6, it is thrown out, by the centrifuge force exerted upon it and caused to engage the flange 31 of the member 1 which is consecl uently driven by reason of such frictiona engagement.

Inasmuch as the ring 3 is not attached at any oint to the cooperating member of the clutc and is of substantiall uniform structure throughout its len th, t e frictional contact between the annu ar faces of the clutch members will be uniformly distributed and will vary in accordance with the speed of shaft-rotation in each direction.

I desire and intend to cover and include herein all variations in form, dimensions and combinations of the arts shown and described that do not e ect a material change in mode of operation or result.

I claim as m invention:

1. The com ination with an annular clutch member and a shaft on which said member is rotatabl mounted, a supporting device keyed to sai shaft, and a concentrically and radially slotted rin mounted upon said supporting device ant expansible by centrifugal force exerted solely through its own weight to engage the annular clutch member.

2. The combination with an annular clutch member and a shaft u on which said member is rotatably mountet of a supportirig device keyed to the shaft, a concentrica y and radially slotted ring mounted upon the sup orting device having its ends connected y a spring which normally clamps the ring to the supporting device and the pull of which is overcome by centrifugal force wheni the shaft attains a predetermined s cc 3. The combination with a shaft havinr a supporting device fastened thereto, anti a normally oose member having an annular flange, of a concentrically and radially slotted split ring mounted upon the sup iorting device inside the flange of said loose member and held against all excc )t radial movement and expansible against the flange by centrifugal force, and a spring for connectin the ends of the ring together.

4. 'lhe combination with a shaft and a divided ring provided with a plurality of similar concentrically curved slots and a plurality of radial slots of such widths as to effect a static balance, said ring being so su )porletl by the shaft as to have no independent rotativemovement, of a normally loose member having an annular lhuwe that projects over the ring to be engaged tliereby when the ring is expanded.

5. The combination with a shaft, a split metal ring having ctmcentrically curved and radial slots and supported by said shaft against independent rotative movement and a spring that connects the ends of the ring to ether, of a normally loose member having a auge that proiects over said ring to be engaged thereby \v ien the ring is ex )andcd by centrifugal force exerted solely through its own weight.

6. The combination with a shaft. and a. normally loose member mounted thereon and having an annular flange, of a metal ring having slots concentric with its inner and outer surfaces, and radial slots extending from the concentric slots to the inner surface of the ring and a supporting member that is fastened to the shaft and upon which the ring is mounted in proximity to the flange of the loose member.

7. The combination with a shaft and a. normally loose member having an annular flange, of a spring ring that is divided at one point and has an otherwise unbroken outer surface in proximity to the annular flange and is provided with a plurality of curved slots extendim through it from end to end and with radial slots between the curved slots and the inner surface, a support for the ring, and means for normally clamping the ring to its sup )ort.

S. In a clutch, an expansible one-piece annular clutch member provided with a. plurality of slots of such relative dimensions and so distributed as to statically balance the member and insure operation thereof by centrifugal force and friction with substantially uniform efficiency for both directions of rdtation.

In testimony whereof, I have hereunto subseribed my name this 28th day of February. 1905.

Aldll lltl KINGSBIRY.

Witnesses '.\l'. 1 ltussau, Bursar llmas.

Ill 

